﻿// <copyright file="ManagedFourierTransformProvider.Scaling.cs" company="Math.NET">
// Math.NET Numerics, part of the Math.NET Project
// https://numerics.mathdotnet.com
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using System;
using Complex = System.Numerics.Complex;

namespace MathNet.Numerics.Providers.FourierTransform
{
    public partial class ManagedFourierTransformProvider
    {


        /// <summary>
        /// Fully rescale the FFT result.
        /// </summary>
        /// <param name="samples">Sample Vector.</param>
        static void FullRescale(Complex32[] samples)
        {
            var scalingFactor = (float)1.0 / samples.Length;
            for (int i = 0; i < samples.Length; i++)
            {
                samples[i] *= scalingFactor;
            }
        }

        /// <summary>
        /// Fully rescale the FFT result.
        /// </summary>
        /// <param name="samples">Sample Vector.</param>
        static void FullRescale(Complex[] samples)
        {
            var scalingFactor = 1.0 / samples.Length;
            for (int i = 0; i < samples.Length; i++)
            {
                samples[i] *= scalingFactor;
            }
        }

        /// <summary>
        /// Half rescale the FFT result (e.g. for symmetric transforms).
        /// </summary>
        /// <param name="samples">Sample Vector.</param>
        static void HalfRescale(Complex32[] samples)
        {
            var scalingFactor = (float)Math.Sqrt(1.0 / samples.Length);
            for (int i = 0; i < samples.Length; i++)
            {
                samples[i] *= scalingFactor;
            }
        }

        /// <summary>
        /// Fully rescale the FFT result (e.g. for symmetric transforms).
        /// </summary>
        /// <param name="samples">Sample Vector.</param>
        static void HalfRescale(Complex[] samples)
        {
            var scalingFactor = Math.Sqrt(1.0 / samples.Length);
            for (int i = 0; i < samples.Length; i++)
            {
                samples[i] *= scalingFactor;
            }
        }
    }
}
